Gravatergiy wizard /totem of the bear bar

I am wondering if with the gravity magic you can make your own weapons lighter so that you could then just cast the spell on say 2 great axes and make them able to be used one in each hand making for a high damage dealing bar. Would that work? 

Several reasons that doesn't work.

1. You can't rage and concentrate at the same time.
2. Adjust density only applies to 1 object at a time.
3. Even if a 2 handed weapon is lighter, it is still 2 handed.

You are not the first to try to dual wield great weapons, and you won't be the last. Currently, there is no RAW way of doing so in 5e.